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IAUC 4370: 1987D; 1987A; 1987B

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                                                  Circular No. 4370
Central Bureau for Astronomical Telegrams
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
TWX 710-320-6842 ASTROGRAM CAM    Telephone 617-495-7244/7440/7444

SUPERNOVA 1987D IN MCG +0-32-01
     A. M. Cherepashchuk, Sternberg Astronomical Institute, cables
the discovery by Nataliya Metlova of a supernova located 15" east
and 27" south of the nucleus (R.A. = 12h17.2, Decl. = +2 22',  equinox
1950.0) of MCG +0-32-01.  On Apr. 2, two plates showed the object
to be fainter than mag 17; on Apr. 20.85 UT, mpg = 14.0.

     H. P. Larson, University of Arizona; S. Drapatz, Max Planck
Institute for Physics and Astrophysics; M. J. Mumma, Goddard Space
Flight Center, NASA; and H. A. Weaver, Space Telescope Science
Institute, report:  "We acquired an infrared spectrum of SN 1987A on
Apr. 16.3 UT from the NASA Kuiper Airborne Observatory (based in
Christchurch).  We used the University of Arizona Fourier-transform
spectrometer in the range 1.5-3.0 mm and at a spectral resolution
of 2 cmE-1; the achieved signal-to-noise ratio in the continuum was
85 in the K photometric band.  The spectrum contains numerous broad,
asymmetric H I lines, including Paschen alpha (1.88 mm), and Brackett
beta (2.62 mm), gamma (2.17 mm), delta (1.95 mm), and epsilon (1.82 mm).
The spectrum also displays two prominent, unexpected features.  One, a
strong emission line near 1.9 mm, may be due to He I.  The second,
a deep (40 percent), broad absorption in the 2.9-mm spectral
region, may be diagnostic of dust containing low-temperature minerals.
Both unexpected features, and most of our observed H I lines,
occur in spectral regions that are strongly obscured by telluric
H2O and cannot therefore be studied from ground-based telescopes."

     Further provisional photoelectric photometry by A. Beresford,
Adelaide, South Australia (20-cm reflector; cf. IAUC 4369):  Apr.
21.46 UT, V = 3.15, B-V = +1.64.

     Visual magnitude estimates:  Apr. 16.42 UT, 3.3 (R. McNaught,
Siding Spring Observatory); 17.72, 3.3 (J. Campos, Durban, R.S.A.);
18.38, 3.2 (McNaught); 19.71, 3.3 (Campos); 20.36, 3.2 (D. A. J.
Seargent, The Entrance, N.S.W.); 21.43, 3.1 (McNaught).

     Visual magnitude estimates provided by J. A. Mattei, AAVSO:
Mar. 8.34 UT, 14.5 (J. Griese, Stamford, CT); 11.36, 14.5 (Griese);
25.34, 14.4: (Griese); Apr. 2.33, 15.5 (R. Royer, Wrightwood, CA).

1987 April 22                  (4370)            Daniel W. E. Green

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